1. Field of the Invention
This invention relates to a four-wheel-drive motor vehicle of transversely-disposed engine type, in which a front differential and a directional change gear for transmitting driving force to rear wheels are disposed coaxially with a certain space left therebetween, especially to a layout of members which extend in the longitudinal direction of a vehicle body below the axle.
2. Description of the Prior Art
For example, Japanese Patent Application Laying Open Gazette No. 63-103735 discloses a new layout of the engine, power transmitting system, etc. in relation to axles for a transversely-disposed engine. According to this layout, an engine is disposed above and in the rear of a front axle where a front differential is arranged, a transmission is connected to the engine through the medium of an intermediate gear or the like and a steering mechanism is arranged below the engine which is in the rear of the axle. As compared with the case where the greater part of the engine and the power transmitting mechanism is located in front of the axle, the above layout lightens the load on front wheels and as a result improves revolvability, steerability, etc. of a motor vehicle.
In the above mechanism, a directional change gear for power transmitting to the rear wheel side in the case of four-wheel-driving is provided on a different axis from the front differential but it is also known that mainly for the purpose of compactness, the front differential and the directional change gear are arranged coaxially on the front axle, with a certain space left therebetween.
In the construction disclosed by the above gazette, a steering mechanism is arranged in the rear of the axle but in the case where an engine is located in the rear of the axle, it is advantageous to arrange the steering mechanism in front of the axle for locating the steering mechanism as near the axle as possible, while preventing interference with an oil pan at a lower end of the engine and ensuring the required road clearance.
In the above case, however, it is required to arrange a steering shaft connected to the steering mechanism in such a fashion that it extends is the longitudinal direction across the axle. Therefore, in laying out it is required to prevent interference with a differential, etc. Also, if the steering shaft is located lower than the differential, etc., the road clearance is reduced and this is undesirable for running of a vehicle. Moreover, if the position of the steering shaft in the direction of vehicle width is excessively deflected to the side away from the central part, such position is undesirable from the aspect of transmittability of steering force, etc.
In the case where a V-type engine is disposed transversely, for example, an exhaust pipe which introduces exhaust from a bank in front of the engine is arranged in such a fashion that it extends rearwardly across the axle from the front of the axle. In such layout of the exhaust pipe, it is required to prevent interference with the differential, etc. and to ensure the required ground clearance. Also, since it is advantageous to locate the exhaust pipe as near the center of vehicle width direction as possible for leading out exhaust, the same problem as in the case of arranging the steering shaft across the axle will arise.